Table 1. Responses of H. armigera larvae from a resistant strain (LF5) and a susceptible strain (LF) to Cry1Ac protoxin and activated toxin.

Strain	Form of Cry1Ac	LC50 (95% fiducial limits) (ng Cry1Ac per g diet)	Resistance ratioa
LF	protoxin	9.1 (1.7–20)	1.0
LF5	protoxin	980 (700–1300)	110
LF	activated toxin	7.5 (2.3–14)	1.0
LF5	activated toxin	290 (180–420)	39

^aLC₅₀ of the each strain divided by the LC₅₀ of the susceptible LF strain